An infusion set has a primary container fluid path from the primary container, and may be attached to an infusion pump. The infusion pump may normally operate in a forward direction to pump fluid from the primary container along the primary fluid path. However, in certain instances it is desirable for the pump to operate in a reverse direction. An occlusion may occur along the fluid path downstream of the infusion pump, such as in part of a tubing downstream of the infusion pump. Depending on the elasticity of the tubing, a significant amount of fluid may accumulate in the tubing. When the occlusion is removed, the stored fluid may be immediately released downstream creating an unintended bolus. Upon detecting the occlusion, the infusion pump may operate in a reverse direction to prevent such an unintended bolus release.
The infusion set may also require connection of a secondary container. A Y connector allows connection of the secondary container. The Y connector may follow a check valve in the primary container fluid path. The check valve prevents the flow of fluid from the secondary container, which may be elevated, into the primary container. In a clinical care setting a Y site is often attached to the infusion set even when no secondary container is attached to the infusion set in order to enable a clinician to attach a secondary container to the infusion set if needed. An infusion set with a Y site connector but without a secondary container attached prevents fluid from flowing in a bi-direction path and only permits fluid to flow from the primary container in a forward direction. In this set-up the conventional check valve may prevent reverse flow even if the secondary container is not attached, and the infusion pump may not operate in the reverse direction. Accordingly, there is a need for an improved Y site check valve system that will enable bi-direction flow of fluid even when a secondary container is not attached.